1. Field of The Invention
This invention relates to stackable boxes designed to be simple in construction, inexpensive to manufacture, and yet allow ease of stacking in a stable configuration.
2. Description of Related Art
Boxes have been designed to be stackable for some time, arising from the necessity of storing or transporting a large number of boxes in a small space. A few representative examples follow:
McLean, U.S. Pat. No. 1,809,523, discloses a foldable, open top, stackable container. Hinged side walls and end walls are held in their open state by means of biasing springs 18 and leaf springs 17. In order to constrain McLean's stacked boxes against longitudinal and lateral slippage, the end walls are provided with mating tabs 19 and notches (unnumbered); the edges of the tabs of the bottom box abut the edges of the notches of the top box to prevent lateral relative movement. Shoulders 20 on the ends of the box's floor 10 abut the inner surface of bottom box's tabs 19 to prevent longitudinal sliding of the top box on the bottom box. McLean's box is complex, unstable in construction, lacks aesthetic appeal, and the interlocking structure has sharp edges which are subject to damage to themselves and others.
Cranston, U.S. Pat. No. 2,501,379, discloses a stackable display tray in which a recessed peripheral edge around the bottom of the tray fits within a complementary recessed lip interior of an identical tray's top peripheral edge. A lattice-work insert is shaped to fit within the tray's interior. Cranston's tray is inefficient inasmuch as the complementary recesses take up a large proportion of the interior volume of the tray, limiting its usefulness.
Voorhis, U.S. Pat. No. Des. 124,755, shows a design for stackable soap bar's having complementary, upwardly extending arches on the top and bottom surfaces, so that the convex arch of the top of the lower bar mates with the concave bottom of the upper bar. Voorhis's bars are not stable, inasmuch as there are no means provided for preventing the arcuate surfaces from sliding laterally relative to each other.
Ruff, U.S. Pat. No. 2,777,597, discloses a stackable tote box having a channel-shaped base whose end edges are welded to an end supporting member 14 which in turn is welded exteriorly thereof to end member 16 in a stepped relationship. End supporting member 14 is of an inverted V-shape; end member 16 includes parallel, V-shaped arches forming a convex peak opposite a concave notch. When stacked, the V-shaped notch of the top box mates with the V-shaped peak of the bottom box to support the top box and to prevent lateral relative movement of the boxes. The inside surfaces of the bottom box's end members 16 abut the outside surfaces of support members 14 of the top box to prevent longitudinal relative movement of the boxes. The box of Ruff is deficient in that it requires many pieces and a labor intensive assembly.